Tabulating apparatus for typewriters or like machines



y 1963 A. DONOFRIO 3,099,343

TABULATING APPARATUS FOR TYPEWRITERS 0R LEDKE MACHINES Original Filed Aug. 5. 1960 2 Sheets-Sheet 1 45 INVENTOR ANTHONYgNOF l0 F1 -2 W M g MEX ea ATTORNEYS United States Pate 3,099,343 Patented July 30, 1963 3,099,343 TABULATING APPARATUS FOR TYPEWRITERS R LIKE MACHHNES Anthony DOnofrio, Overhill Road, West Hartford, Conn. Continuation of application Ser. No. 47,332, Aug. 3, 1960 This application (lot. 2, 1962, Ser. No. 230,026 9 Qlaims. (Cl. 197-127) This application is a continuation of Serial No. 47,332, filed August 3, 1960, now forfeited.

This invention relates to tabulating apparatus for typewriters or like machines; more particularly it relates to talbulating apparatus having mechanisms for establishing the extent of tabulating movement in accordance with marks on a form whose progress is to be controlled, or in accordance with preset tabular stops; and specifically it relates to tabulating apparatus having operator controlled mechanism for permitting the retention of preset tabular stops during form controlled operation.

Conventional 'tabulating apparatus requires the presetting of tabular stops for establishing the limit of carriage movement after the initiation of tabulating movement. In the tabulating apparatus shown in copending application Serial No. 837,391 (now Patent 3,020,996), every tab stop is set, and after a tab movement is initiated, signals generated by marks sensed from a form during tabulating movement are effective to actuate a tab blade into the path of a stop on the tab rack whose position corresponds to the position of the mark sensed, thereby, limiting carriage movement. In that every stop is preset in the latter apparatus, it is necessary to clear the tab rack and selectively set desired ones of the tab stops where conventional rather than form controlled tabulating operation is desired. This procedure is time consuming and therefore undesirable.

In accordance with the present invention mechanism is provided under operator control whereby the state of the stops in the tab rack is immaterial during form controlled tabulating operation. That is, during form controlled operation, both set and unset tab stops are operative in cooperation with the tab blade which is movable in response to a mark generated signal to terminate movement. When conventional operation is desired however, only the manually preset ones of the stops in the rack are operative to terminate tabulating movement. In other words, predetermined stops, manually set during conventional operation, need not be disturbed; nor do any unset stops have to be moved to set position when going from conventional to form controlled operation.

In accordance with the invention the throw of the tab blade during form controlled operation is such that it may engage unset tab stops as well as set stops. When switching to conventional operation an interposer is activated to limit the throw of the tab blade such that it may engage only set tab stops.

\An object of the invention therefore is in the provision of a form controlled tabulating device operative with set and unset tab stops.

Another object of the invention is in the provision of means for controlling the throw of a tabular stop blade to limit its effectiveness only with set stops.

Another object of the invention is in the provision of an improved mark detecting circuit.

A further object of the invention is to provide mechanism which permits of the retention of set tab stops when tabulating movement is under control of marks on a form.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein:

FIGURE 1 is a perspective view of tabulating mechanism in accordance with the invention;

FIGURE 2 is a side elevational view of the tabular blade and throw control mechanism;

FIGURE 3 is a rear elevational view of the tabular blade and throw control mechanism;

FIGURE 4 is a block diagram of the tabulating control circuitry; and

FIGURE 5 is a schematic diagram of the circuitry of FIGURE 4.

Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the several views and wherein is illustrated a preferred embodiment, there is shown in FIGURE 1 a tabulating mechanism comprising a tabular link 10 adapted to be powered forwardly, as viewed in the figure, through connection with an associated bell crank (not shown) upon depression of a tabular key. The tabular is pivotally connected as at 11 to a lever arm 12 fast on a shaft 13 mounted in the typewriter frame whereby, as link 10 moves forwardly, shaft 13 is rocked clockwise. Shaft 13 also has secured thereto a rack bar lifting lever 14 adapted to engage an car 15 on, and to rock counterclockwise, a rack bar lifting arm 16 pivoted on the type writer escapement frame (not shown) and having an upper arm 17 extending beneath a rack rail 18. When arm 16 rocks counterclockwise, the rack rail 18 raises a rack bar 19 out of engagement with the typewriter escapement pinion 20 thereby freeing the typewriter carriage for movement in tabulating direction as indicated by arrow 21. Lever arm 12 is also provided with an extension 22 adapted to be engaged by a slot 23 formed in a latch member 24 pivoted as at 25 on a bracket 26 secured to the typewriter frame. A spring 27 interposed between the rear end of member 24 and an ear (not shown) on the bracket 26 urges the latch member 24 clockwise so that when lever arm 12 rocks clockwise extension 22 will move forwardly until it reaches slot 23 whereupon spring 27 will pivot latch member 24 clockwise, latching lever arm 12 and shaft 13 in actuated position, whereby the rack will be held out of engagement with the escapement pin-ion.

The tabulatin-g mechanism also includes a support mounted on the carriage comprising upper and lower rack bars 31 and 32, respectively, formed with aligned transverse grooves which are spaced longitudinally of the rack bars at letter space intervals. A plurality of tabular stops 33 are mounted in the grooves and are detentable in set and unset positions. In accordance with the invention the tab stops are made wide enough in the front to near direction so as to engage, when in an unset position, a tabular blade 34 when the blade is moved to its operative position. In the form shown the tabular blade is pro vided with a boss 35 secured as by a set screw to the blade mounting means comprising a shaft 36. The shaft 36 is mounted for axial and rocking movement in bearing lugs 37 and 38 comprising part of the typewriter center stop 39. The tabular blade 34 is normally biased into a retracted position out of engagement with the tab rack by :a spring 41 suitably secured thereto and to the typewriter frame. The tabular blade 34 is adapted to be moved into the path of a tab stop 33 through connection as at 42 with the armature 43 of a solenoid 44 suitably mounted on the typewriter frame. The tab blade is also constituted by a rearwardly and laterally extending car which as more clearly shown in FIGURES 2 and 3 mounts a set screw 45 which, when the tab blade is activated forwardly, engages the center stop 39 to limit the throw of the tabular blade in a conventional manner. In accord ance with the invention the tabular stops 33 are made wider whereby the throw determined by the set screw 45 and center stop 39 is such that the blade 34 will normally engage unset stops as well as set stops 33. In accordance with the invention an interposer solenoid 46 is mounted on a bracket 47 secured to the center stop 39. The armature 48 associated with the solenoid is coupled to an interposer 49 pivoted as at 50 on the bracket 47. Interposer 49 is biased from between the forward end of set screw 45 land the center stop 39 by a spring 51 secured to the solenoid mounting bracket 47 and the lower end of the interposer 49. When the solenoid '46 is energized, as will hereinafter appear, the interposer 49 will move between the set screw 45 and the center stop 39 and limit the throw of the tabular blade 34 to a distance such 1 at it can only engage set stops, designated 33 in FIGURE 1, in the tab rack. While a solenoid actuated interposer 49 is preferred in that it requires a of changes to the conventional Royal construction, it should be understood that the interposer 49 could be mechanically actuated as well. The tab blade 34 is also connected by a link 52 to the latch member 24 to thereby permit the rack 19 to re-engage the escapement pinion 20. In the normal position of the parts the tabular blade abuts center stop 39, and boss 35 is axially spaced from bearing lug 38; spring 27 being inelfective to move tab blade 34 axially to the right through link 52 because of the abutment of extension 22 with latch member 24.

The above arrangement of tabulating parts difiers from the Royal electric typewriter construction in that the tab blade 34 is solenoid actuated rather than being linked for actuation to and by rock shaft 13. It differs also in the addition of the interposer solenoid 46, and further, by the addition of a form C tab latch switch 53 provided on the typewriter frame and disposed so that its movable contact 53b (FIGURES 4 land is actuated to its' other than normal position by movement of lever arm '12 to actuated position.

Energization of solenoid 44 whereby the tab blade 34 is actuated iorwardly is effected when a mark is detected during tabulating movement, or immediately upon the initiation of a tabular operation, depending on whether ganged switches 54, 55 and 56 (FIGURES 4 and 5), operable by a two position key 57 positioned on the front panel of the typewriter, are an auto or manual position. As illustrated in FIGURES 4 and 5 the switches are in auto position. In this position the solenoid 44 is connected in circuit with a flip-flop circuit via contacts 54a and 54b. Solenoid 46 is connected in an open circuit, contact-s 56a and 56b being open, and a lamp 58' is energized, contacts 55a and 55b connecting it across a power source.

When key 57 is depressed to manual position both the tab solenoid and the interposer solenoid are connected via switch contacts 54!) and 54c and contacts 56:: and 56b to the stationary contact 53c of the tab latch switch 53. Also lamp 58 will be extinguished. As will be understood, when the extent of tabulating movement is being conventionally controlled by preset tab stops 33', those preset tab stops will be manually set by a set key in a conventional manner.

When the extent of tabulating movement is determined by marks on a form, signals resulting from sensed markswill eifect the energization of solenoid 44. The mark sensor comprises a photoconductive cell 59 (FIGURE 5 As more particularly described in copending application Serial No. 837,391 (now Patent 3,020,996), the lamp 58 is positioned :on the typewriter frame to direct a spot of light, preferably the size of the tabulating control marks on the form, to the area immediately in front of the typewriter printing station. Due to the curvature of the platen the light is difiiusely reflected from the form. The photoconductive cell 59 is positioned from to A3" of the platen within the volume of diffusely reflected light. In i at the resistance of the cell increases with decreases in light intensity within its field of vision, the cell responds 4 to decreases in light intensity resulting from the passage of marks past the typewriter printing station.

With further reference to FIGURES 4 and 5 the circuitry for controlling the tabular blade comprises a mark detector circuit 61 which includes the pho-toconductive cell 59. Circuit 61 generates signals in response to light variations at the printing station including light variations due to marks passing the printing station. The output of the mark detector circuit is filtered by a filter circuit 62 and is amplified in an amplifier circuit 63 whose output is employed to actuate the flip-flop circuit 64.

Referring particularly to FIGURE 5 there is shown the improved mark detector circuit in accordance with the instant invention comprising an NPN transistor 65 having its base electrode connected, via the photoconductive cell 59 and a base current limiting resistor 66, to the junction 67 of resistors 68 and 69 serially connected between the collector and ground. This bias connection places the transistor operating point approximately midway between collector current minimum and maximum values. Increases in cell resistance due to decreases in ambient light, to decreases in light as a result of paper variations, and to decreases in light due to passage of. marks past the vision of the photocell, will cause a decrease in base current and a resulting decrease in the voltage drop across resistor 69 with the result that junction 67 and the collector will swing in a positive direction with respect to the emitter. The consequence of this swing will cause more collector and base current to flow thereby to increase the voltage drop across resistor 69 to its initial value.

As shown in the figure, the positive pulses resulting from changes in the cell resistance at the collector are coupled through a condenser 71 to the filter section 62. The value of condenser 71 is chosen such that pulses of frequencies below the filter rejection band are not passed. Such pulses will be those due to changes in ambient light conditions which occur slowly. The filter section 62 comprises twin T sections designed to reject pulses having frequencies in the power frequency range. The positive signals passed by the filter, which are constituted by high amplitude, relatively high frequency pulses and by low amplitude, relatively high frequency pulses due to detected marks and paper variations, respectively, are passed by a coupling condenser 72 to the first stage of the amplifier 63 comprising the base of an emitter follower transistor 73, employed for impedance matching purposes as will be understand by those skilled in the art. The positive pulses at the emitter of transistor 73 are coupled via a condenser 74 to the base electrode of a PNP transistor 75. As shown the base of transistor 75 is connected to the collector supply source through a rheostat 76 and fixed resistor 77. The rheostat is employed to adjust the bias level of transistor beyond that necessary to achieve maximum collector current flow such that the transistor collector current is at maximum value. In effect transistor 75 will therefore operate (to clip the base portions of the signal pulses applied thereto, thereby eliminating low amplitude pulses due primarily to paper variations; passing only the signal pulses due to detected marks. Adjustment of rheostat 76 also permits the reduction of signal voltage amplitudes developed by marks less than a predetermined width to ineffective levels. The output of the clipper transistor stage 75 is RC coupled to the base electrode of an inverter amplifier 7 8 whereby a posi tive output pulse will be developed at the collector thereof. In order that leakage currents due to temperature increases will be obviated, the emitter is connected to the collector supply source via a resistor 79 and to ground via a sufiicient number of diodes 80 to provide the proper impedance necessary to normally maintain the emitter sufiiciently negative to prevent leakage currents but not sufiicient to prevent conduction by signal applied to the base electrode.

The amplifier output is coupled via a condenser 81 and a diode 82 poled to pass positive pulses to the base of a PNP transistor 83 which together with a PNP transistor 84 comprises flip-flop circuit 64. In that the base of transistor :84 is normally connected to ground via the contacts 53a and 53b of the tab switch the flip-flop circuit can only be responsive to mark generated signals after initiation of a tab operation.

Assuming that manual control is desired an array of tab stops 33 will be preset in accordance with a desired tabular format and switches 54, 55 and 56 will be in manual position; hence lamp 58 will be extinguished, and solenoids 44 and 46 will be connected to stationary tab switch contact 53c. Further flip-flop circuit 64 will be disabled through disconnection of power from the collector of transistor 84. When a tab operation is initiated, with the resulting closure of contacts 53b and 530 of tab switch 53, both the tab solenoid 44 and the interposer solenoid 46 will be immediately energized; the latter faster acting solenoid being operative through its armature to limit the throw of the tabular blade into the path of set tab stops 33' only, whereby tabular operation will be terminated upon encountering a set tab stop 33'.

If automatic operation is desired, all that is required is to move switches 54, 55, and 56 to auto position. This lights lamp 58, enables flip-flop circuit 64 and renders solenoid 46 inefiective thereby to permit the tabular blade 34 to move sufficiently to engage unset stops 33 as Well as set stops 33'. When a tab operation is initiated the actuation of tab switch 53 conditions transistor 34 by removing ground from the base thereof, thereby permitting the flip-flop circuit, in response to a positive pulse resulting from a mark detected at the printing station, to switch state and energize the tab solenoid 44, whereby the blade 34 engages the stop, set or unset, corresponding to the mark sensed, effecting termination of tabulating movement in the space immediately after the mark detected.

In the event that the carriage, at the termination of a carriage return, positions the form to the right of the printing station, the dark material of the platen will be before the printing station. Calling for a tab when the carriage is so positioned will cause the cell to develop a negative pulse when the left edge of the form passes the printing station. A diode 85 is provided to pass this negative pulse to ground. If this safety feature were not provided, the condensers of the system could not return to normal in time to respond to the detection of a mark closely adjacent the left edge of the form. With the diode the system can sense White to black variations only one increment removed from a black to white variation.

It should be understood that the foregoing disclosii'e relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example herein chosen for the purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.

The invention claimed is: 1. A printing machine comprising a frame and a carriage movable relative to said frame for supporting a worksheet for movement past the printing station of said machine, said carriage having tabular stops mounted thereon and adapted to be moved from unset to set positions,

a tabular blade mounted on said frame for movement into engagement with set and unset tabular stops,

means for initiating tabulating movement of said carriage, said worksheet having marks selectively printed thereon for controlling the progress of said carriage tabulating movement,

means for generating signals in response to passage of marks past said printing station,

circuit means responsive to the initiation of tabulating movement and to said signals,

and a tabular blade control solenoid responsive to the output of said circuit means for moving said tabular blade.

2. Apparatus as recited inclaim 1 further comprising an interposer for limiting the throw of said tabular blade for engagement by set tabular stops, an interposer solenoid for actuating said interposer, and means for disabling said signal responsive circuit means and for conditioning said interposer solenoid and said tabular blade control solenoid for energization immediately upon initiation of tabulating movement whereby said tabular blade will terminate carriage movement upon encountering a set stop.

3. In a typewriter comprising a frame,

a carriage for supporting a worksheet for movement relative to the printing station of said typewriter, tabular stops mounted on said carriage positionable in set and unset positions,

a tabular blade mounted on said frame for movement into the path of said stops,

means for moving said tabular blade into the path of stops in unset positions,

and means for limiting the movement of said tabular blade whereby it can move only into the path of stops in set position.

4. Apparatus for generating signals in response to the passage of marks past the printing station of a business machine comprising a transistor having serially connected resistors in its collector circuit,

a photoconductive cell responsive to light variations at said printing station connected to the base of said transistor and to the junction of said series resistors whereby the collector current flowing is maintained stabilized between maximum and minimum values,

means coupled to the collector of said transistor for filtering out low frequency variations in collector cur-rent,

means coupled to said filter means for discriminating against high frequency lo-w amplitude variations in col-lector current,

and means coupled to said last named means for amplifying high frequency high amplitude variations in collector current.

5 A typewriter having a frame,

a carriage movably mounted on said frame and adapted to support a form for movement past the printing station of said typewriter,

tabulating stops mounted on said carriage,

a tabular blade,

signal responsive means for moving said tabular blade into the path of set and unset tabulating stops, said form having marks thereon opposite selected tabulating stops,

means for initiating tabular movement of said carriage,

means for photoelectrically detecting said marks at the instant of passage past said printing station comprising a transistor having serially connected resistors in the collector circuit thereof,

a photoconductive cell mounted on said frame Within a volume of light reflected from said form opposite said printing station,

means connecting said cell between the base of said transistor and the junction of said resistors,

and control means responsive to collector current variations resulting from light variations due to the passage of marks through the field of vision of said photoconductive cell for actuating said signal responsive means, whereby said tabular blade will engage -a tabulating stop and halt tabnlating movement.

6. Apparatus as recited in claim 5 further comprising means for disabling said control means, means for ac tuating said tabular =blade upon initiation of tabular movement of said carriage, and means for limiting the throw of said tabular blade into the path of set tabulatingstops only.

7. Apparatus for deriving signals corresponding to marks in a business form comprising a photoconductive cell responsive to light variations Within its field of vision,

a business machine instrumentality for moving said form relative to said cell whereby said marks pass through the field of vision of said cell,

a transistor having resistance in its collector circuit selected to set the transistor operating point between maximum and minimnm'values of collector current.

means connecting said cell between the base and collector of said transistor,

and means connected to the collector of said transistor responsive to collector current variations due to the passage of marks through the field of vision of said cell.

8. Apparatus for deriving signals corresponding to marks on a business record comprising a photoconductive cell responsive to light variations within its field of vision,

a data processing instrumentality for moving said record relative to said cell whereby said marks pass through the field of vision of said cell,

a transistor having resistance resistors in its collector circuit selected to set the transistor operating point between maximum and minimum values of collector current,

means connecting said cell between the base and collector of said transistor and means connected to the collector of said transistor responsive to collector current variations due to light variations in the field of vision of said cell, said last named means comprising means for discriminating against collector current variations corresponding to ambient light variations, and means for discriminating against collectorcurrent variations corresponding to light variations due to passage through said field of vision of marks of less than a predetermined Width.

9. Apparatus for deriving signals corresponding to marks on a business record comprising a photoconductive cell responsive to light variations within its field of vision,

means for moving said business record relative to said cell whereby said marks pass through the field of vision of said cell,

a transistor having series connected resistors in its collector circuit,

means connecting said cell between the base of said transistor and the junction of said resistors whereby light variations within the field of vision of said cell cause transient variations in collector current,

means for filtering low frequency transient variations in collector current corresponding to ambient light variations,

means for amplifying high frequency transient Variations in collector current corresponding to the passage of marks through the field of vision of said cell,

and adjustable means for passing only high frequency transient variations in collector current of predetermined amplitude to said amplifying means.

References Cited in the file of this patent UNITED STATES PATENTS 1,333,690 Waldheim Mar. 16, 1920 2,181,992 Gher-tman Dec. 5, 1939 2,332,033 Welker Oct. 19, 1943 2,902,137 Toeppen Sept. 1, 1959 

1. A PRINTING MACHINE COMPRISING A FRAME AND A CARRIAGE MOVABLE RELATIVE TO SAID FRAME FOR SUPPORTING A WORKSHEET FOR MOVEMENT PAST THE PRINTING STATION OF SAID MACHINE, SAID CARRIAGE HAVING TABULAR STOPS MOUNTED THEREON AND ADAPTED TO BE MOVED FROM UNSET TO SET POSITIONS, A TABULAR BLADE MOUNTED ON SAID FRAME FOR MOVEMENT INTO ENGAGEMENT WITH SET AND UNSET TABULAR STOPS, MEANS FOR INITATING TABULATING MOVEMENT OF SAID CARRIAGE, SAID WORKSHEET HAVING MARKS SELECTIVELY PRINTED THEREON FOR CONTROLLING THE PROGRESS OF SAID CARRIAGE TABULATING MOVEMENT, MEANS FOR GENERATING SIGNALS IN RESPONSE TO PASSAGE OF MARKS PAST SAID PRINTING STATION, CIRCUIT MEANS RESPONSIVE TO THE INITATION OF TABULATING MOVEMENT AND TO SAID SIGNALS, AND A TABULAR BLADE CONTROL SOLENOID RESPONSIVE TO THE OUTPUT OF SAID CIRCUIT MEANS OF MOVING SAID TABULAR BLADE. 